add dart format workflow

checks code has been formatted with dart format on push and pull request

adds a note in README for contributors

.github/workflows/dart.yml

@@ -0,0 +1,21 @@
+name: Dart Format
+
+on:
+  pull_request:
+  push:
+
+jobs:
+  analyze:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up Dart
+        uses: dart-lang/setup-dart@v1
+
+      - name: Install Pub Dependencies
+        run: dart pub get
+
+      - name: Verify Formatting
+        run: dart format --output=none --set-exit-if-changed .

README.md

@@ -217,6 +217,7 @@ This is an open-source project. Contributions are welcome!
 - Use `const` constructors where possible
 - Keep functions small and focused
 - Avoid premature abstractions
+- Run dart format on all changes before submitting
 
 ## Support